PM Designer troubleshooting: panel not found, download fails, communication errors

PM Designer cannot find the panel

Over USB

1. Driver. With the panel connected and powered, open Device Manager. If the panel is missing or shows a warning, run WinUSB4NuVCOM.exe from the Usb folder of the PM Designer installation as administrator, then reconnect. This is the cause in most USB cases.
2. Cable and port. Use a data-capable cable under 3 m on a port of the PC itself, not a hub or docking station. Try a second cable before anything else.
3. Panel state. The panel must be running its application or sitting in Panel Setup. A panel stuck in the System Loader does not answer USB downloads; load a PRP from USB stick instead (see below).
4. Another program holds the port. Close the PLC programming software, terminal programs and a second PM Designer session.

Over Ethernet

1. IP address. On the panel, open Panel Setup > General and read the IP address, subnet mask and gateway (Section 20.2.2). Put the PC on the same subnet and ping the panel from a command prompt. No reply means a network problem, not a PM Designer problem.
2. Duplicate address. A second device with the same IP answers some pings and not others. Change the panel to a free address outside the router's DHCP range.
3. Firewall. A corporate firewall or endpoint agent on the PC can block the download port. Test with the Windows firewall off for a minute, or from a bare laptop.
4. Wrong panel. Several panels on the same network with the factory default address all answer to that address; set each one before connecting it.

The download starts and then fails

• Transfer drops part-way. Switch Mode to Safe Mode in the Download dialog so the data is buffered in RAM and written to flash only when complete (Section 18.3.1). Then fix the physical cause: a cable, a USB hub, a Wi-Fi link to the panel's switch.
• "Model does not match". The project is compiled for a different panel model. Set the correct model in Panel > General Setup, recompile, download again.
• Panel asks for a developer password you do not know. The panel holds a project with a different developer password. You need that password from whoever programmed it; the default is 000000000. Without it, the only alternatives are a PRP file of the existing application (which carries the matching password) or a factory reset by Cermate's service channel. There is no bypass, and we do not provide one.
• Runtime too large. The compile result shows a size above the panel's limit (about 20 MB on the K series, 50 MB on the T series). Shrink pictures to native resolution and remove unused ones from the Picture Database.
• Panel OS too old for the project. Tick Runtime Data and System Programs so the OS is updated with the application, or load a PRP that contains both.

The panel shows a communication error with the PLC

The message names the link and often a status code. Work through the physical layer first, then the parameters, then the addresses.

1. Prove the cable with on-line simulation from the PC (Tools > Run On-line Simulation) using the same settings. If the PC cannot talk to the PLC either, the problem is wiring, the PLC port configuration or the driver choice, not the panel.
2. Check the parameters on the panel itself. Panel Setup > Link n shows the serial parameters or IP address the panel is actually using (Sections 20.2.5 and 20.2.6). If someone edited them there, "Communications Settings" on the General page decides whether the downloaded defaults or the panel's own values win.
3. RS-485 wiring and termination. Swap A and B if in doubt, and check the PLC station address matches the PLC Address in the Parameter page.
4. Siemens S7 over Ethernet. Rack and slot must match the CPU, and every data block the panel reads must have "Symbolic access only" (optimized block access) unchecked in the PLC project (Section 3.4.11).
5. Modbus driver role. "Device/Slave" drivers make the panel the master talking to a slave PLC; "Master" drivers make the panel the slave. Picking the wrong family gives silence, not an error (Section 3.4.9).
6. One bad address. A single object reading an address outside the PLC's configured range can hold the whole link in error. Check the link status from a macro with LINK_STS; the codes are listed in Chapter 3.

The project will not compile

• Address out of range: the driver does not support that register type or number. Compare with the driver's accessible memory table, or try the address in the Address Input Keypad, which only offers valid types.
• Start-up screen missing: General Setup points at a screen number that was deleted or renumbered.
• Macro errors: a label without a colon, an IF without ENDIF, a FOR without NEXT, or a constant that looks like an address (write 40001K to force a constant). The Build List jumps to the line.
• Tag errors: a global tag name must start with an underscore; a local one must not; names cannot start with a digit or match a macro keyword.
• Memory: data loggers, alarm logging and recipe blocks compete for battery-backed RAM; the compiler reports when it cannot allocate them. Reduce samples or move recipe storage to flash backup.

Problems on the panel itself

• Touch is offset or dead. Panel Setup > Touch Panel runs the calibration (Section 20.2.3): touch the dots with a blunt stylus, never a screwdriver or pen.
• Panel boots to Panel Setup instead of the application. Set Run AP After Power On to True on the General screen, press OK, then Run.
• Cannot get into Panel Setup from the running application. Allow To Run Panel Setup is False. Either download a version with the flag enabled or use the System Loader (hold the top-left corner for 3 seconds during power-up) and choose Run.
• "Battery backed RAM data error! All recorded data are cleared!" at power-up. The backup battery is flat or has been disconnected; recipes, alarm history and logged data in battery-backed RAM are lost. Replace the battery, restore recipes from the flash backup or a PRD file, and keep logs flowing to files or a USB stick.
• Clock drifts or resets. Set Time/Date in Panel Setup; the RTC Adjustment field corrects a steady drift in seconds per day. A clock that resets every power cycle is again the battery.
• Screen stays black. Screen Saver Time turns off the backlight after the set number of minutes; touch the screen. If brightness was lowered in the General screen, raise it there or in the System Loader.
• Lost operator password. A level 8 user can open the password table from a function button configured with Show Password Table (Section 20.1.6). If nobody has a level 8 login, the project file is the only place the passwords are readable; the panel does not display them.

Recovering a panel that no longer boots

1. Hold the upper-left corner of the screen while applying power until the panel beeps; the System Loader appears.
2. If you have a PRP of the application, put it on a USB stick, choose Update from File and select it. The OS and application are rewritten and the panel restarts normally.
3. If you have only the project, build a PRP with Panel > Build Panel Runtime Package on the PC first, or set the panel's IP address in the loader's General screen and download from PM Designer over Ethernet.
4. Format Disk C is a last resort for a corrupted file system; it erases everything on the panel's built-in disk and needs a level 8 password.

The project file is lost

If Configuration Data was ticked on the last download, Panel > Upload recovers a PLF that imports as a panel application and can be edited. If not, the panel contains only compiled runtime and the project must be rebuilt. The PM Designer Automatic File Recovery feature (Project > Information & Protection) keeps timed backups of unsaved work in a Backup folder under the user's profile, which is worth checking after a crash. For every machine you ship, archive the .pm4 file, a PRP of the released version and the developer password together.